Many programs generate files named with a string of numbers (often a Unix timestamp) to ensure uniqueness. The number 1595406539 translates to Wednesday, July 22, 2020 , suggesting this file may have been created or timestamped on that specific date. Security and Maintenance
If it is in a temporary folder (like C:\Users\[User]\AppData\Local\Temp ), it is likely a leftover from a past installation or scan. If it is in C:\Windows\System32 and you did not put it there, use caution. 1595406539.vac
Use Microsoft Defender or Malwarebytes to perform a "Custom Scan" on the specific folder containing the file to ensure it isn't malicious. Many programs generate files named with a string
Valve's anti-cheat system occasionally generates temporary or cached data files. These files are typically stored in game directories or the Steam folder to help identify unauthorized modifications to game files. If it is in C:\Windows\System32 and you did
The software Virtual Audio Cable uses the .vac extension for some of its configuration or driver-related components. If you have audio routing software installed, this file may be a legitimate part of that toolkit.
, or did it appear after installing a specific game or audio tool ? How to Run a Full Scan Using Windows Security
Because the filename is non-standard, it is important to verify its safety: